The invention relates to a lock cylinder comprising a cylinder core which has a key channel for insertion of a key that is provided with a profiling, the lock cylinder also comprising at least one feeler member disposed in the cylinder core and acted on by a spring, the feeler member being held by the spring in a blocking position when a key is not inserted into the key channel, and the lock cylinder further comprising a blocking member which is held in a blocking position that blocks rotation of the lock cylinder when the feeler member is in its blocking position, the feeler member being drivable against the return force of the spring into a release position by the profiling of the matching key when this key is inserted into the key channel, in which release position the blocking member can be displaced into a position in which it unblocks the cylinder core.
The invention also relates to a locking device consisting of a lock cylinder and a matching key.
A lock cylinder with a matching key is described by DE 30 24 929. The lock cylinder has a cylinder housing that has a mounting bore in which the lock cylinder is enclosed, it being possible for the cylinder core to be rotated by insertion of a matching key into the key channel in order to rotate, upon insertion of the key, a locking member which is coupled to the cylinder core and by which a lock can be actuated. When no key is inserted, the cylinder core is blocked against rotation by tumblers. A multiplicity of tumblers, each of which has a housing pin and a core pin, lie in pin bores of a profile portion of the cylinder housing, these pin bores being aligned with core pin bores of the cylinder core. When no key is inserted, the housing pins cross over the dividing line between the cylinder core and the cylinder housing. In the generic cylinder core, there is a cylindrical feeler member, which is displaceable in the axial direction. The feeler member is held in a blocking position by a spring, in which position it prevents a displacement into a release position of a blocking member formed as a blocking bar. If the matching key is inserted into the key channel, not only the tumbler pins are sorted in such a way that the housing pins no longer cross over the dividing line. When the matching key is inserted, the feeler member is also displaced into a release position. For this, the feeler member senses a profile rib of the pin with the end face of the feeler member opposite from the end face acted on by the spring. When the key is fully inserted, the feeler member is displaced into a position such that the blocking member can be displaced into a position that unblocks the cylinder core. The cylinder core can then be turned.
DE 16 78 096 describes a lock cylinder having a cylinder housing and a cylinder core that is rotatably mounted in a bore of the cylinder housing. The core has a key channel into which a key can be inserted. The key shank of the key has notches for sorting core pins. The core pins have heads that are formed in the shape of the ridge of a roof and can enter into obliquely extending notches in the key shank and thereby assume a defined rotational position. The inserted matching key gives the core pins a rotational position such that projections of a blocking member can enter into radial cut-outs in the core pins, so that the blocking member, which effects a rotational blocking of the cylinder core when a key is not inserted, can move away radially inwards into a position in which it unblocks the rotatability of the cylinder core.
DE 36 09 473 A1 describes a lock cylinder in which the cylinder core is blocked against rotation by means of a double-armed blocking lever, which is pivotable into an unblocking position by insertion of a matching key. The lever is acted on by a compression spring and is controlled by a feeler pin that senses a profiling of the wide side of the key.